Telephone-transmitter.



E. B. CRAFT.

TELEPHONE TRANSMITTER.

APPLICATION FILED JULY9,1910.

1,096,} 53 Patented May12,1914

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PATENT @FFEQE.

EDWARD B. CRAFT, 0F HACKENSACK, NEW JERSEY. ASSIGNOR TO WESTERN ELECTRIC COMPANY, OF NEW YORK,'N. Y., A CORPORATION OF ILLINCIS.

TELEPHONE-TRANSMITTER.

Specification of Letters ?atent.

Patented May 12, tea 4.

curing and insulating one of the electrodesthereof.

In accordance with the invention the structure for supporting the electrode comprises a tubular bolt held in an opening in a piece of the frame of the transmitter, the

.dianieter of the opening being larger than that of the bolt and the bolt 'being held in central position by means of'an insulating washer or washers seated on one or both sides of the frame piece, and secured against lateral displacement. The holes in said washers are of the same diameter as the outside diameter of the bolt and means, preferably a nut, is provided for clamping the bolt inpiace. The rear electrode is provided with a stud which is adapted to slip loosely through the hole in the bolt where it is finally held rigidly in place by means of aset screw or other fastening means. Electrical connection to the rear electrode may be made by means of a terminal washer clamped between the bolt and frame plate. To prevent the washer from rotating, it may be provided with a raised point or ridge engaging a notch in the underneat side of the bolt head.

The invention will be fully understood by reference to the accompanying drawings, in

which-- Figure l lsa rear elevation, with the easing removed, of a telephone transmitter em-' hodying the invention; Fig. 2 is an enlarged fragmentary view in section along the line 22 of Fig. 1; and Fig. 3 is a detail sectional view of thebridge piece on the line 33 of Fig. 1.

In the drawing, the frame 1 of the transmitter is provided with the usual mouthpiece 2 and bridge iece' 3, a casing 26 serving to cover the worhing parts and to support the instrument. A diaphragm 4 is seated in the frame 1 but insulated therefrom by a washer 5 which may be of paper, the diaphragm having :1 turned up circumferential flange 6 flattened at its extreme edge. In The center of the diaphragm is a depression 7 adapted to be engaged by the rounded end of a stud 8 which is secured to the front electrode 9 of a granular button unit 10, the radius of curvature of the stud end being slightly greater than that of the depression, so that contact will be made at the perimeter of the depression. The stud 8 has a flan e 27'for1ning a shoulder against which t e free upturned ends 28 of a spring 11 bear. This spring is held by but insulated from the bridge piece 3 by means of screws 12 and a tapped bar 13, a screw 14 being provided for connecting a wire to make electrical connection with the front electrode.

The back electrode of the granular button 10 is provided with a stud 15 adapted to slip freely through a hole in a tubularbolt 16. This bolt is of smaller diameter than an opening 17 in the bridge piece 3, but is held centrally positioned in said opening and therefore out of contact therewith by means of insulating washers 18, preferably of mica. These washersare seated as shown in depressions on either side of the bridge piece. The bolt is held in place by a nut 19 and electrical connection to the back electrode through the bolt is provided for by a terminal washer 2O lying under the head of the bolt and held in place by it. This washer is prevented from turning with respect to the bolt by means of a notch 21 under the head of the bolt engaged by the washer at a raised point or ridge 22, which is formed in the washer. One of the insulating washers 18 is of irregular contour, as shown in Fig. 1, so that whenseated in the bridge piece it cannot turn with the bolt and the washer 20 is provided with a raised point 23 engaging a hole in the insulating washer to prevent turning with respect to the bridge piece. A screw 24 is provided for making the electrical connection to the rear electrode.

In assembling the parts of this transmi ter the tubular bolt 16 and its several washers are put in place and the nut 19 turned until the bolt is held rigidly in place. The granular button unit 10 is then inserted with its stud 15 lying loosely in .place and the spring 11 fastened in place with its free ends engaging the shoulder of the stud back of the rim 9, The diaphragm 4 is then placed loosely in its seat against the paper was er 5 and the bridge piece, with the granular button and spring held thereby, fastened. securely to the frame 1 with the end of the front electrode stud 8 engaging the depression. 7 attire center of the diaphragm. At this ime the spring 11 will give somewhat, but Will exert the proper pressure against the diaphragm and the position of the diaphragm in its seat will be adjusted to conform to any slight irregularities in the formotion of the bridge and the position of the granular button therein. At the some time the stud 15 of the back electrode will be pushed liaolnvardly and assume its proper position in the bolt opening. Finally the back eieotrode may be rigidly secured in place by means of the set screw l mi ing thus described my lI1VGDLlOI1,'\VlIilL I claim r i. In a telephone transmitter, the combination of an electrode provided with a stud, u frame piece for holding said electrode in place, it tubular bolt said frame piece loaving' on opening larger in diameter than said bolt and through which the bolt extends, insulating" Washers seuted in depressions in either side of said frame piece aboiiit said opening and adapted to hold said bolt in central position with inspect to said open ing, means for rigidly clamping said bolt in place in the opening, and means for adjustobly fastening stud in the opening through said tubular bolt.

2111 a telephone transmitter, the combi nation with an electrode provided with a, stud by which it is ;1(l2L]')l-(;(i to be supported and 5, bridge piece hin ing an opening thro'cgli which. said sit extends, oi tubular bolt fitting over stud, said bolt be ing oi smaller dHi-XHCiIQl than the opening in said bridge pioc insulaw in depressions in either piece about openi'. hold said bolt in central positi Contact with the Walls of s means for clamping said and 2. terminal Washer lield in Contact with said bolt 3. In a telephone trzmozn nation with an electrode oro stud and a frame piece for hold trode in place, of a tubuler ooit said stud, said frame p hm. ing of larger diameter than the said bolt, insulating washers pressions in either side of said about said opening and edapi bolt in central position opening, one of said insulating; ing of irregular shape, means For said bolt in place, a terminal W, and in Contact with said bolt Withwprojoction shaped asher.

4:. In a. telephone t1i1l1Sl1" nation with on (ilCClTQfl Silldfifld a. frame-piece trode in place, of a tu said stud and insuleti opening in said frame, Washer cloinped by plate, said washer he adopted to lit into a I to prevent rotation 01 In witness whereof, I, L my name this 7th day 0,.

EDWA

Vfitnesses:

IRVXNG lVAGQOl H ll/lORG/LN Moi-inn i 5, 

